1. Field of the Invention
The preferred embodiments of the present invention relate, inter alia, to a friction clutch, to a vehicle equipped with the friction clutch, and/or to an assembly method of the friction clutch.
2. Description of Related Art
The following description sets forth the inventor's knowledge of related art and problems therein and should not be construed as an admission of knowledge in the prior art.
Conventionally, a friction clutch has been used for vehicles, such as, e.g., two-wheeled motor vehicles. Japanese Unexamined Laid-open Patent Application Publication No. 2008-157390 (hereinafter referred to as “Patent Document 1”) discloses a friction clutch comprising a friction plate engaged with a clutch housing, a clutch plate engaged with a clutch boss, and a pressure plate that presses the friction plate and the clutch plate in a direction in which they come in contact with each other. The friction plate is equipped with a plate main body and a friction material formed on the surface of the plate main body. When the friction plate and the clutch plate contact each other, a frictional force is generated between both of those plates mainly by the aforementioned friction material, which transmits the force between the clutch housing and the clutch boss.
In the aforementioned friction clutch, the friction plate and the clutch plate are placed alternately along the axial direction of the clutch. Among these plural friction plates and clutch plates, the plate arranged most radially outward of the clutch shaft is a friction plate. The pressure plate, by moving in the axial direction of the clutch shaft, presses the outermost friction plate from the outside. The pressure plate is configured to rotate together with the clutch boss.
In this kind of friction clutch, however, in some cases, an oscillatory phenomenon called “judder” can occur in, e.g., the so-called half clutch state.
The description herein of advantages and disadvantages of various features, embodiments, methods, and apparatus disclosed in other publications is in no way intended to limit the present invention. For example, certain features of the preferred embodiments of the invention may be capable of overcoming certain disadvantages and/or providing certain advantages, such as, e.g., disadvantages and/or advantages discussed herein, while retaining some or all of the features, embodiments, methods, and apparatus disclosed therein.